Patient-matched instrumentation and methods

ABSTRACT

A patient-matched cutting block including a surface or point contact features adapted to at least partially conform to or reference a patient specific anatomy. The cutting block having guide slots configured for guiding the movement of cutting tools relative to the patient specific anatomy or features configured to mate to and guide standard cutting guides relative to patient specific anatomy in order to form plateau and eminence resections of the patient specific anatomy.

CROSS REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. patent application Ser. No.13/821,582 filed Sep. 25, 2013, which is a U.S. National Phase ofInternational PCT Application No. PCT/US2011/056380 filed Oct. 14, 2011,which claims the benefit of U.S. Provisional Patent Application Ser. No.61/393,175 filed Oct. 14, 2010, the entire contents of which eachapplication incorporated herein by reference.

TECHNICAL FIELD

This disclosure relates to patient-matched instrumentation.

BACKGROUND

Patient-matched or patient-specific implant guides are used duringorthopaedic procedures to accurately insert pins, guide cuts, and placeimplants. The patient-matched guides are generally based on datareceived from an MRI or CT scan of the patient and rely on matching ananatomic feature for correct positioning of the guide during a surgicalprocedure.

Generally these patient matched guides are held in place by pins orscrews to reduce the risk of slipping during surgery. Pins are typicallyinserted into healthy bone outside of the resection area to ensurecontinued stability and to avoid interference with surgical instrumentsused during the procedure.

There remains a need for a less damaging solution that reduces theamount of damage to healthy bone and retains at least a portion of thetibial eminence during use of surgical instrument guides whilemaintaining the ease of use and speed associated with patient-matchedguides.

There also remains a need for improved structural rigidity of thefeatures guiding cutting tools relative to patient specific anatomy.

There also remains a need for a means within patient matchedinstrumentation of making resections which result in the appropriatebalance soft tissue tension.

There also remains a need for patient matched instrumentation able toorient and guide the additional resections required for preserving atleast a portion of the proximal tibia.

SUMMARY

In one general aspect, a patient matched cutting block includes asurface or point feature adapted to at least partially conform to orreference a patient specific anatomy, and a plurality of guide slotsconfigured for guiding the movement of cutting tools relative to thepatient specific anatomy to form plateau and eminence resections of thepatient's anatomy.

Implementations can optionally include one or more of the followingfeatures. For example, the patient specific surface or point contactfeature is established in pre-surgical planning based on imaging data ofthe patient's anatomy. The patient matched cutting block furtherincludes one or more apertures configured to guide the placement ofprovisional fixation pins, and wherein the apertures contain positioncontrol elements configured to control the depth of the provisionalfixation pins. The patient matched cutting block may further compriseretractor features detachably coupled to the cutting block andconfigured to retain soft tissue away from the guide slots. Theplurality of guide slots may include surfaces that facilitate horizontalmedial and lateral plateau resections and medial and lateral verticaleminence resections of a proximal tibia. The patient matched cuttingblock may further comprise guide slots for facilitating vertical andhorizontal anterior tibial eminence resections of the proximal tibia.

In another general aspect, a patient specific tibial cutting guideincludes a central portion configured to at least partially overlayanterior and superior portions of the proximal tibia, a plurality ofoutrigger portions extending from the central portion and configured toat least partially overlay medial and lateral articulation surfaces ofthe proximal tibia, and a plurality of wing portions extending mediallyand laterally from the central portion and configured to extend at leastpartially around medial and lateral sides of an anterior face of theproximal tibia, wherein the central portion and the plurality ofoutrigger portions define guides configured for guiding a cutting toolto form vertical and anterior eminence resections of the proximal tibiaand the plurality of wing portions define guide slots for guiding acutting tool to form horizontal plateau resections of the proximaltibia.

Implementations can optionally include one or more of the followingfeatures. For example, one or more of the central portion, the pluralityof outrigger portions, and the plurality of wing portions may includeone or more surfaces or point contacts adapted to at least partiallyconform to or reference a corresponding surface of the proximal tibia.The one or more surfaces or point contacts is established inpre-surgical planning based on imaging data of the patient's proximaltibia. The patient specific tibial cutting guide may further compriseone or more apertures defined in the central portion or the plurality ofoutrigger portions and configured to guide the placement of provisionalfixation pins. The plurality of wing portions may include retractorfeatures configured to retain soft tissue away from the guide slots. Thepatient specific tibial cutting guide may further comprise reinforcingelements at least partially embedded in one or more of the centralportion, the plurality of outrigger portions, or the plurality of wingportions.

In another general aspect, a system includes a patient matched cuttingblock or a patient specific tibial cutting guide and a standardinstrument attachable to the patient matched cutting block or thepatient specific tibial cutting guide to assist in the configuration ofand guidance of a cutting tool during a bone resection procedure.

In another general aspect, a method of resectioning a proximal tibiaincludes securing a patient matched instrument to a patient's proximaltibia and using the patient matched instrument to guide one or morecutting guides relative to the proximal tibia to form horizontal medialand lateral plateau resections, medial and lateral vertical eminenceresections.

Implementations can optionally include one or more of the followingfeatures. For example, securing the patient matched instrument to thepatient's proximal tibia may comprise using one or more fixation pins tosecure the instrument in a particular location relative to the tibia,and wherein one or more holes formed in the tibia during the securingstep are removed during resectioning.

Instrumentation and methods, including patient-matched instrumentationand methods, for facilitating orthopaedic procedures including kneearthroplasty procedures such as bi-cruciate retaining knee arthroplastyprocedures are further described herein.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows an unresected, proximal tibia.

FIG. 2 shows one implementation of a patient-matched cutting guidepositioned on the proximal tibia of FIG. 1.

FIG. 3 shows the proximal tibia of FIG. 1 after resection.

FIG. 4 is a top plan view of the resected proximal tibia of FIG. 3, anda cutting profile for a vertical anterior eminence resection.

FIG. 5 is a top plan view of a resected proximal tibia according toanother implementation, and a cutting profile for a vertical anterioreminence resection.

FIG. 6 is a top plan view of the patient-matched cutting guide andproximal tibia of FIG. 2.

FIG. 7 is a top plan view of the patient-matched cutting guide andproximal tibia of FIG. 2 after resection.

FIG. 8 shows another implementation of a patient-matched cutting guide.

FIG. 9 is another view of the patient-matched cutting guide of FIG. 8.

FIG. 10 shows another implementation of a patient-matched cutting guide.

FIG. 11 shows another implementation of a patient-matched cutting guide.

FIG. 12 shows another implementation of a patient-matched cutting guide.

FIG. 13 shows another implementation of a patient-matched cutting guide.

FIG. 14 shows the patient-matched cutting guide of FIG. 12 with certaincomponents removed.

FIG. 15 shows reinforcement structures of the patient-matched cuttingguide of FIG. 12.

FIG. 16 shows another view of the patient-matched cutting guide of FIG.12.

FIG. 17 shows another view of the reinforcement structures of FIG. 15.

FIG. 18 shows another view of the patient-matched cutting guide of FIG.12.

FIG. 19 shows another view of the reinforcement structures of FIG. 15.

FIG. 20 shows another implementation of a patient-matched cutting guide.

FIG. 21 shows another view of the patient-matched cutting guide of FIG.20.

FIG. 22 shows a proximal tibia after resection.

FIG. 23 shows a proximal tibia after resection.

FIG. 24 shows a proximal tibia after resection.

FIG. 25 shows another implementation of a patient-matched cutting guide.

FIG. 26 shows two views of a proximal tibia after primary resections.

FIG. 27 shows two views of a proximal tibia after provisionalresections.

FIG. 28 shows another implementation of a patient-matched cutting guide.

FIG. 29 shows a proximal tibia and a fixation pin.

FIG. 30 shows another implementation of a patient-matched cutting guide.

FIG. 31 shows the patient-matched cutting guide of FIG. 30 in additionto a distal portion of a femur and a femoral trial.

FIGS. 32 through 35 show additional implementations of patient-matchedcutting guides.

FIG. 36 shows a proximal tibia after resection.

FIG. 37 shows another implementation of a patient-matched cutting guide.

FIGS. 38 through 42 show additional views of the patient-matched cuttingguide of FIG. 37.

FIG. 43 shows a proximal tibia after resection.

FIG. 44 shows another view of the patient-matched cutting guide of FIG.37.

FIGS. 45 and 46 show another implementation of a patient-matched cuttingguide.

FIGS. 47 through 50 show another implementation of a patient-matchedinstrument.

FIG. 51 shows another implementation of a patient-matched instrument.

FIGS. 52 through 60 show various views of a standard,non-patient-matched instrument that can be used in conjunction with thepatient-matched instruments of FIGS. 47 through 51.

FIGS. 61 through 72 illustrate some of the steps of one example of anarthroplasty procedure using the instrumentation shown in FIGS. 47through 67.

FIG. 73 shows a view of a supplemental instrument that can be used inconjunction with the standard instrument of FIGS. 52 through 60.

It should be understood that the drawings are not necessarily to scaleand that the disclosed implementations are sometimes illustrateddiagrammatically and in partial views. In certain instances, detailswhich are not necessary for an understanding of the disclosure or whichrender other details difficult to perceive may have been omitted. Itshould be understood, of course, that this disclosure is not limited tothe particular implementations illustrated herein.

DETAILED DESCRIPTION

FIG. 1 shows a proximal portion of a tibia 100 including, among otherthings, a tibial eminence 110 that is flanked on a medial side by amedial articulation surface 111 for articulation with a medial femoralcondyle and flanked on a lateral side by a lateral articulation surface112 for articulation with a lateral femoral condyle. The tibial eminence110, among other things, may provide attachment sites for anterior andposterior cruciate ligaments. Other anatomy, although not necessarilyspecifically shown, may also be present, such as a meniscus, patellartendon, collateral ligaments, and other soft tissues.

As shown in later figures and described below, in some knee arthroplastyprocedures, one or more portions of the proximal tibia are resected tofacilitate the positioning and/or attachment of orthopaedic implantssuch as tibial baseplates and/or separate or integral tibial inserts. Insome implementations, such as those relating to bi-cruciate retainingknee arthroplasty procedures discussed below, the medial and lateralarticular surfaces, as well as an anterior portion of the tibialeminence, are resected, while a substantial portion of the tibialeminence remains, including, in some implementations, portions of thetibial eminence 110 functioning as anterior and posterior cruciateligament attachment sites. In some instances, properly positioning andorienting these resections to achieve optimal positions and orientationsfor the tibial implant(s) can be difficult and time consuming.

FIG. 2 shows a patient-matched instrument 200 positioned on the proximaltibia of FIG. 1. The patient-matched instrument 200 shown in FIG. 2 is atibial cutting guide with a plurality of slots and other guide surfacesfor guiding the movement of cutting tools such as reciprocating andoscillating saw blades with respect to the proximal tibia. In theparticular implementation shown in FIG. 2, the tibial cutting guide 200includes guide surfaces 210 for guiding horizontal medial and lateralplateau resections, medial and lateral vertical eminence resections, andvertical and horizontal anterior tibial eminence resections. The tibialcutting guide 200 of FIG. 2, when properly positioned and oriented onthe patient's tibia, establishes the positions and orientations of thesesix resections. As discussed in more detail below, the tibial cuttingguide 200 of FIG. 2 includes several surfaces 205 that are adapted to atleast somewhat conform to or reference the unique geometry of theparticular patient's anatomy, these surfaces 205 substantiallyfacilitating a precise or substantially precise positioning andorienting of the patient-matched instrument of the patient's anatomywith respect to a desired position and orientation, which, in someimplementations, may have been established in pre-surgical planningstages based on imaging data of the patient's specific anatomy or otherinformation.

Other implementations can include patient-matched tibial cutting guides,other cutting guides, and other surgical instrumentation for guidingother resections or other bone modifications with respect to aparticular patient's anatomy. Other implementations may includedifferent numbers, positions and orientations of cutting guide slots orother guide surfaces or point contact features, such as, for example, aprobe having a small radius (i.e., a radius less than the radius of theanatomy contacted) that without deformation, contacts the anatomy in asingle point, as desired.

The patient-matched tibial cutting guide 200 shown in FIG. 2 includes acentral portion 220 overlying to at least some extent anterior andsuperior portions of the proximal tibia, two outrigger portions 230extending from the central portion over the medial and lateralarticulation surfaces, and two wings 240 extending medially andlaterally from the central portion around medial and lateral sides ofthe anterior face of the tibia. In this particular implementation, thecentral portion 220 and outriggers 230 define guide slots and otherguide surfaces 210 for the vertical eminence and anterior eminenceresections, and the two wings 240 define guide slots 210 for thehorizontal plateau resections. The tibial cutting guide 200 shown inFIG. 2 includes guide surfaces 210 that are captured to at least someextent. Other implementations of patient-matched instruments may includeslots or other guide surfaces or structures that are completelycaptured, not captured at all, or other combinations.

FIGS. 3 and 4 show the proximal tibia 100 of FIG. 1 after resectionsusing the patient-matched tibial cutting guide 200 of FIG. 2. As shownin FIGS. 3 and 4, the medial 310 and lateral 320 plateau resections, aswell as the horizontal anterior eminence resection 330, aresubstantially co-planar, while the medial 340 and lateral 350 verticaleminence resections and the vertical anterior eminence resections 360are substantially perpendicular to the plateau resections. The curvedsections 370 joining the vertical eminence resections to the horizontalplateau resections shown in the particular implementation of FIG. 3 arecaused by two of the fastening pins discussed further below. FIG. 5shows a top plan view of the resections from an alternativeimplementation where the vertical anterior eminence resection 360 isprovided by a cutter having a curved profile.

Other resection layouts, positions and orientations of resections arealso possible and within the scope of the present disclosure. Forinstance, in some implementations, the plateau resections 310, 320 donot have to be coplanar and the vertical eminence resections 340, 350could be non-parallel and/or extend at non-perpendicular angles from theplateau resections 310, 320.

In some implementations utilizing the cutting guide of FIG. 2, the twoplateau resections 310, 320 are made first, followed by the two anterioreminence resections, with the two vertical eminence resections 340, 350being performed last, although, in other implementations, otherresection orders could be used. In some implementations, this order ofresections may preserve pin fixation longer during the procedure.

The patient-matched tibial cutting guide 200 of FIG. 2 may include twoor more apertures, 260 for receiving fixation pins to secure the guideto the proximal tibia 100. In the particular implementation shown, twosecondary, optional apertures 250 are located on distal ends of theoutriggers 230 and are oriented vertically to receive pins 255penetrating surfaces of the medial and lateral articulation surfaces.Two primary apertures 260 are located in the central portion and areoriented horizontally to receive pins 265 penetrating anterior surfacesof the proximal tibia 100. FIG. 6 shows the location of the two verticalpins 255. FIG. 7 shows the location of the two horizontal pins 265. Inthis particular implementation, the apertures are located proximate thepatient-matched surfaces on the bone facing sides of the instrument,although other locations are also possible.

The horizontal pins 265 shown in FIGS. 2 and 7 extend just to theposterior side of the proximal tibia. In the implementation shown byFIG. 7, exterior surfaces on the central portion of the cutting guide(i.e. surfaces that do not face the bone) are calibrated to the specificpatient and to the specific length of pin to be used such that the pinsjust reach the posterior side of the proximal tibia. In this particularimplementation, the exterior surface 205 on the central portion 220contacts shoulders (not shown) on each pin to limit theanterior-posterior insertion depth of each pin 265 to a precise,pre-determined depth, although other structures and pin/cutting guideinteraction mechanisms could be utilized in other implementations tolimit pin-depth to a desired depth. In some implementations, theportions of the “exterior” surface for contacting the pin could berecessed into the block compared to the surrounding “exterior” surfaces,although, in other implementations, these surfaces could be flush withrespect to one another or arranged in other manners. In someimplementations, alternative mechanisms can be used to calibrate the pindepth with respect to the exterior surface or other portions of thecutting guide. For instance, in some implementations, laser etched linesor other indicia could be used to indicate the anterior-posterior depthof the pin with respect to the patient-matched exterior surface of thecutting guide.

In some implementations, this depth can be set by examining MRI or otherimage data specific to the patient's anatomy and, in conjunction with adesired pin length, determine where the exterior surface of thepatient-matched cutting guide (or portions of the exterior surface, orother structures or mechanisms) is positioned to properly limit thedepth of the pins. Various automated, semi-automated, or manualprocedures and systems could be used to process imaging data orotherwise determine the proper insertion depth.

In some, although not necessarily all, implementations, it may bedesirable to use the horizontal pins (or other structures associatedwith the cutting guide) to protect the tibial eminence from notching,undercutting or other unintended resection or damage by the cuttinginstruments and other instruments used during the surgical procedure. Insome, although not necessarily all, of these implementations, it may bedesirable to precisely control the anterior-posterior depth of thehorizontal pins (or other horizontal, vertical or other oriented pins orother fastening mechanisms) such that the pins extend along the entire(or substantially entire) anterior-posterior length of the tibialeminence to provide such protection without substantially extendingposterior to the tibia (which could undesirably impact on surroundingsoft tissue or other anatomy). In such instances, the depth controlmechanisms discussed above may be desirable.

In some implementations, the patient-matched tibial cutting guide may bepackaged, shipped and/or otherwise associated with the proper length ofpins to be used for the specific patient. In these or otherimplementations, the correct pin length could be indicated on thepatient-matched guide itself (or on the guide's packaging).

In some implementations, the particular positions and orientations ofthe pin receiving openings in the patient-matched instrument are suchthat once all of the resections have been completed, the cavities formedby the pins inserted through those openings do not remain in thepatient's bone. In other words, in some implementations, the pins usedwith the patient-matched instrument only extend through bone that areremoved by the resections. In some implementations, pin length may alsobe adjusted or optimized to reduce or eliminate the incidence of pinholes in the remaining bone. For instance, in some implementations, thevertical pins may be positioned such that they do not extend below thelevel where the horizontal plateau resections are made.

FIG. 8 shows an alternative implementation of a patient-matched tibialcutting guide 400 having additional features. The cutting guide of FIG.8 includes a visualization window 425 positioned in the central portion420 of the guide 400 for visualizing anterior portions of the tibialeminence. In the particular implementation shown, the visualizationwindow 425 can be revealed by breaking off a frangible portion of theguide (not shown).

The cutting guide 400 of FIG. 8 also includes retractor features 490positioned on distal ends of the two wings 440. In some implementationsthe retractor features 490 may facilitate retaining soft tissues awayfrom the operation site, to allow better visualization and to protectthose soft tissues from damage. In the particular implementation of FIG.8, the retractor features 490 include hollow portions 495, which mayhelp to dampen at least somewhat the forces exerted on the cutting guide400 by the soft tissues retained by the retractor features 490. In someimplementations, this may help avoid potentially undesirable deflection,deformation or other alteration of the shape, position and/ororientation of the cutting guide or particular portions of it, such asthe wings 440 and guide surfaces on those wings. In otherimplementations, other shapes and configurations of retractor features490 are possible, or, in other implementations, retractor features areunnecessary.

In some implementations, certain features of the patient-matched guide,such as the retractor features 490 and visualization window 425 featureof the patient-matched tibial cutting guide 400 of FIG. 8, may beremovable or otherwise reconfigurable. For instance, as shown in FIG. 9,the retractor features 490 may include a series of perforations 491 thatmay facilitate the removal of the retractor features 490 after use or ifthey are not desired for the particular procedure. In otherimplementations, other frangible or non-frangible connections,structures or other mechanisms can be used to allow portions of thepatient-matched instrument to be broken away, removed or otherwiserepositioned.

In some implementations in which portions of the patient-matchedinstrument are intended to be broken off during the procedure, it may bedesirable to utilize frangible connections that do not result inexcessive (or any) debris when broken to avoid contamination of thewound site. In some implementations, the particular geometry of thefrangible connection may lower the chances of small pieces contaminatingthe wound when the frangible portion is removed. In these or otherimplementations, the patient-matched instrument itself can be formedfrom one or more materials that reduce the likelihood of debrisresulting from severing a frangible connection.

In some implementations, the frangible features can be formed in apatient-matched instrument formed in a selective laser sintering processusing Nylon-12 as the manufacturing material. In these or otherimplementations, the power of the laser could be varied during themanufacturing process to create lines or regions of material in whichthe bonding strength is reduced, allowing certain portions of thepatient-matched instrument to be broken off more easily.

In some implementations, the removable features can be removed after useto avoid interference with later portions of the procedure. In someimplementations, removal of the removable features may allow greateraccess or visualization of portions of the patient-matched instrument,anatomy, or other items that were not easily accessible or were not ableto be easily visualized prior to removal of the removable feature. Forinstance, in some implementations, removal of a removable feature fromthe patient-matched instrument may allow access to other features of thepatient-matched guide for guiding or otherwise performing otheroperations or portions of operations on the anatomy using other featuresof the patient-matched guide that were originally hidden by theremovable feature. In these or still other implementations, removal of aremovable portion or portions may facilitate adjusting the guides orother features of the patient-matched instrument.

FIG. 10 shows a patient-matched tibial cutting guide 600 that includes abuilt in drop rod connector 680. In some implementations, this can be anintegral part of the patient-matched instrument, whereas, in otherimplementations, this can be a feature that can be added and/or removedfrom the patient-matched instrument at the user's discretion and at thetime of his or her choosing. In some implementations, the drop rodconnector 680 can be secured to the patient-matched guide 600 using afrangible connection similar to those described above for the removableretractor features. The drop rod connector 680 shown in FIG. 10facilitates the connection and alignment of a drop rod 684 with thepatient-matched tibial guide 600, which, in some implementations, mayfacilitate visualizing the alignment of the patient-matched instrument600 with an anatomic or mechanical axis of the tibia or other structureof the tibia or other anatomy. This visualization may allow forcross-checking of orientation of the patient-matched guideintraoperatively.

FIG. 11 shows another implementation 700 of a patient-matched tibialcutting guide that includes a drop-rod connector 780 that has auser-operated mechanism with two protrusions 785 that, when pinchedtogether, holds a drop rod (not shown) in the aperture of the connector780, ensuring that it is in a desired position and orientation withrespect to the cutting guide. In the particular implementation of FIG.11, the user operated mechanism 785 and at least portions of theaperture of the drop-rod connector 780 are formed from a material thatis compliant such that when the protrusions are pinched together theaperture deforms at least slightly to tighten its fit around a drop rodextending through it. In some implementations, the entirepatient-matched instrument may be made from a compliant material that issufficiently sized, shaped, and has other characteristics such that someportions of it can be deformed whereas other portions are more resistantto deformation (e.g., in some implementations, it may be desirable forportions defining and/or supporting the cutting guide surfaces or pointcontact features (some of which are described above and below) to beresistant to deformation to ensure accurate alignment of the tibialresections). In some implementations, other portions of thepatient-matched instrument or features associated with thepatient-matched instrument may be made of material or in a sufficientshape or other configuration to take advantage of a compliant portion ofthe construct.

In some implementations, such as the implementation shown in FIG. 12,the patient-matched instrument 800 may include reinforcements toincrease the rigidity of the instrument or certain portions of theinstrument. For instance, in the implementation of FIG. 12, manyportions of the patient-matched tibial cutting 800 guide may be formedfrom Nylon-12 using a selective laser sintering process (SLS), and, atleast conceptually, could be subject to undesired deformation,especially when a cutting blade or other cutting device is being used inconjunction with the instrument. In at least some of these instances, itmay be desirable to include reinforcements 801 in the patient-matchedinstrument to help increase the rigidity of the device. In theparticular implementation of FIG. 12, these reinforcements 801 aremostly embedded in the instrument, and are not visible from the outside(except for the two posts 802 extending superiorly from anteriorportions of the outriggers).

In some implementations, the reinforcements may be formed from materialshaving different properties than the rest of the patient-matchedinstrument. Thus, in some implementations, the majority of thepatient-matched instrument may be made from Nylon-12 using an SLSprocess whereas the reinforcements may be formed from surgical gradestainless steel or other suitable materials. In some implementations,the reinforcements may be formed from traditional manufacturing methods,and used as a scaffold around which the rest of the patient-matchedinstrument is formed using SLS or other manufacturing techniques used toform a patient-matched instrument. In other implementations, both thereinforcements and the rest of the patient-matched instrument may beformed using SLS or other rapid production technologies, with, in someimplementations, the reinforcements formed first using a first materialand the rest of the patient-matched instrument formed second using asecond material. In other implementations, the reinforcement portionsand the rest of the patient-matched instrument may be formedsimultaneously.

In other implementations, such as the implementation shown in FIG. 13,it is not necessary to include reinforcement materials and thepatient-matched instrument 900 may be formed from a single material, yetstill be sufficiently rigid.

FIG. 14 shows a patient-matched tibial cutting block 1000 configured toreceive reinforcement members, but without those reinforcement membersin place. In some implementations, the patient-matched instrument couldbe formed through SLS or other rapid production techniques first, andthe reinforcement members could be introduced later (either manually orusing automation) into the patient-matched instrument, such as bysliding cylindrical reinforcements into cylindrical holes formed in thepatient-matched instrument.

FIGS. 15, 17 and 19 show the reinforcement members 801 and 801A from theimplementation of FIG. 12. In some implementations, the reinforcementmembers 801 and 801A may be custom positioned depending on the patient'sanatomy and other aspects of the particular patient's planned surgicalprocedure, whereas in other implementations, the reinforcement members801 and 801A may have a “standardized” portion around which all of thepatient-matched instruments of a particular type or size are built. Insome implementations, the reinforcement members 801 and 801A may be anoptional part of the patient-matched instrument, and could be includedwhen certain other features of the patient-matched block are customized.For instance, in some implementations, the reinforcement members 801Athat are positioned to extend along the wings of the patient-matchedinstrument may only be necessary when the guide slots are not capturedat distal ends.

In the particular implementation shown in FIGS. 15, 17 and 19, thereinforcement members 801 are formed from stainless steel dowel pins,although, in other implementations, other materials could be used.

As shown by FIGS. 16 and 18, the reinforcement members 801 or materialsused in some implementations of the patient-matched instrumentsdescribed herein could be used for additional or alternative functionsto solely providing reinforcement to the instrument. For instance, inthe implementation of FIG. 16, one of the central reinforcement members803 also functions as a horizontal stop to prevent a reciprocating sawfrom penetrating too deeply when making the vertical medial and lateraleminence cuts, and also to prevent a saw from advancing into the body ofthe patient-matched instrument. In some implementations, the centralreinforcement member 803 works in conjunction with the two horizontalfixation pins to limit certain aspects of the resections. In otherimplementations, reinforcement members 801 can be strategicallypositioned in additional or alternative locations to provide stops forother cuts.

FIGS. 20 and 21 show another implementation of a patient-matched tibialcutting guide 1100 that, like the guide 200 of FIG. 2, includes guidesurfaces 1110 for medial plateau, medial and lateral eminence, andvertical and horizontal anterior eminence resections, but, unlike theguide of FIG. 2, does not include a lateral wing or guide surfaces of alateral plateau resection. FIG. 22 shows the resections that can be madeusing the cutting guide of FIGS. 20 and 21, although, in someimplementations, the cutting guide 1100 might be used to make only someof these resections. In some implementations, the patient-matched tibialcutting guide 1100 of FIGS. 20 and 21 could be used in combination withother patient-matched or standard instrumentation to complete the restof the tibial resections, depending on the type of knee arthroplastyprocedure. For instance, in some implementations, a standard lateralcutting guide could be used to guide the lateral plateau resection, andmay include structure for referencing the existing medial plateauresection, other resections, and/or pin holes to align the lateralplateau resection to the other resections.

FIG. 23 shows a proximal tibia with medial plateau 1120 and medial 1150and lateral 1140 eminence resections, but with anterior portions of theeminence still intact. Leaving anterior portions of the eminence intact,at least in earlier stages of the procedure, may reduce in someinstances the risk that the eminence could fracture or otherwise becompromised during the procedure, which may be a risk in someprocedures, such as procedures in which trials and/or balancingtechniques are used to evaluate the medial and/or lateral resections.FIG. 24 shows a proximal tibia 100 with only medial plateau 1120 andeminence 1150 resections, illustrating the possibility of using thepatient-matched cutting guide of FIGS. 20 and 21 for a uni-condylar kneearthroplasty.

FIGS. 25 and 28 show patient-matched instrumentation, in this particularimplementation a patient-matched tibial cutting block 1200, for guidingprovisional resections on a patient's anatomy, such as, in thisparticular instance, a provisional medial plateau resection and aprovisional medial eminence resection. In some instances, it may bedesirable to make relatively shallow provisional resections in thepatient's anatomy, such as the proximal tibia 100, to afford anopportunity to evaluate certain characteristics of those provisionalresections and/or possible primary resections prior to actually makingone or more of those primary resections, such characteristics including,for instance, one or more of depth, medial/lateral position,anterior/posterior position, varus/valgus rotation, internal/externalrotation, and/or posterior slope. As one non-limiting example, FIG. 26illustrates primary resections made after evaluation utilizing theprovisional resections of FIG. 27.

FIG. 29 illustrates that, in some implementations, after provisionalresections are made, the provisional patient-matched cutting guide canbe removed, although, optionally, a pin or pins 1265 (such as a pin thathad been used to temporarily secure the provisional guide to the bone)can be left in place to facilitate the positioning and/or securing ofother instrumentation to the bone.

FIG. 30 illustrates another implementation of a patient-matched cuttingguide 1300 that incorporates a trialing or balancing feature 1335 forevaluating one or more aspects of existing or possible resections to thepatient's anatomy. Although FIG. 30 illustrates a patient-matchedinstrument, standardized cutting guides incorporating similar featuresare also possible. In the particular implementation illustrated in FIG.30, the trialing/balancing feature 1335 is a trial articular surface forarticulation with a femoral trial 120 (see, e.g. FIG. 31) to facilitateevaluating and/or predicting balance, tightness, biomechanics and/orother aspects of the knee if the primary resection is made using thecutting guide(s) incorporated into the instrument of FIG. 30. In thisparticular implementation, the trial articular surface replicates or atleast substantially replicates the expected final position andorientation of at least the medial portion of a tibial implant implantedonto the primary resections defined by the instrument of FIG. 30.

In some implementations, the instrument 1300 of FIG. 30 may be one of akit of instruments for evaluating possible primary resections ofdifferent characteristics, such as different depths and/or posteriorslopes. For instance, the instrument of FIG. 30 provides trialing andcutting guides for a primary resection of 0 degrees of posterior slopethat adds −2 mm of depth to a standard resection depth; whereas FIG. 32illustrates an instrument 1400 providing a 0 degree, 0 mm primaryresection and FIG. 33 illustrates an instrument 1500 providing a −3degree, 0 mm primary resection. Other variables could also beincorporated into such a kit. For instance, in some implementations, theset of instruments could additionally or alternatively include variousvarus/valgus rotations, internal/external rotations, medial/lateralpositions, and/or other variables. In some implementations, a kit couldbe custom made for a particular surgeon and/or patient, and, in someimplementations, may include only a subset of certain desiredbalancing/trialing options.

FIGS. 34-36 illustrate an implementation 1600 in which, afterbalancing/trialing and once an acceptable instrument is identified, theselected instrument can be further pinned to the proximal tibia, ifdesired, and one or more resections can be made using that instrument.In the particular implementation shown in FIG. 36, lateral resectionshave also been performed, which, as mentioned above, could beaccomplished with the same instrument used for the medial resections ora different instrument, one or both of which may or may not be matchedto the particular patient.

FIG. 37 illustrates an implementation 1700 similar to the instrumentshown in FIG. 30, but that also includes a detachable component 1780.The detachable component 1780 is an anterior eminence resection guide,which, initially is not positioned for use but is positioned to avoidinterfering with the trialing/balancing process that, in someimplementations, may occur prior to resection of anterior portions ofthe eminence. For instance, in some implementations, when positioned foruse, the anterior eminence resection guide 1780 might be prone tointerfering with portions of the femoral trial component 1735. In thisparticular implementation, the anterior eminence resection guide 1780 isinitially positioned where it is not prone to interfering with thetrialing/balancing process, and, once that process is completed, can bedetached (e.g. through frangible connections or other suitablestructures or mechanisms) and reconnected to the instrument in theproper position and orientation for use. FIGS. 38 through 42 illustratethe anterior eminence resection guide 1780 as it is first attached, andthen subsequently detached at a frangible connection points, and thensubsequently placed into a position and orientation for guiding theresection of anterior portions of the eminence.

In the particular implementation of FIGS. 38 through 42, a frangibleconnection 1782 between the anterior eminence resection guide 1780 andthe rest of the instrument includes a series of breakable pins (see,e.g., FIG. 44, which shows the pins after breaking), although otherfrangible or non-frangible mechanisms are also possible. For instance,in some implementations, the connection is not designed to be breakable,but otherwise allows the component to be moved from a first position toa second position (e.g. a hinge or other mechanism).

In the particular implementation of FIGS. 38 through 42, the anterioreminence resection guide 1780 is connected and properly positioned andoriented for use by inserting the post 1781 of the anterior eminenceresection guide 1780 into a cylindrical hole 1783 and snapping theresilient groove 1784 onto one of the horizontal reinforcement membersdiscussed above, a portion of which may extend through the cylindricalhole (FIG. 41). Once in position, the instrument 1700 may be placed onthe tibia for use (FIG. 42). The connection between the groove andhorizontal member, in some implementations, may function to both securethe two structures together as well as properly orient them with respectto one another. Other connection and orienting mechanisms are alsopossible. FIG. 43 illustrates the proximal tibia 100 after resectionusing the instrument shown in FIGS. 38 through 42.

FIG. 44 shows an interior (bone facing) side of the patient-matchedinstrument 1700 of FIG. 37. As shown in this particular implementation,the instrument 1700 includes a patient-matched surface 1706 thatconforms to or references the unique geometry of the patient's anatomyto ensure that the instrument 1700 is properly positioned and orientedwith respect to the particular patient's anatomy. These and otherpatient-matched surfaces can be included to contact various portions ofthe bony or other anatomy of the patient to facilitate positioning andorienting the instrument on the particular patient's anatomy. Forinstance, in the implementation shown in FIG. 2, the instrumentadditionally includes patient-matched surfaces on the undersides of atleast portions of the outriggers extending from the main body of theinstrument. Other numbers, locations and orientations of patient-matchedsurfaces are also possible. Other implementations may include pointcontact surfaces.

FIGS. 45 and 46 show another implementation in which the patient-matchedinstrument 1800 includes patient-matched surfaces 1806 on the main body1820, the outriggers 1830 and the wings 1840 of the instrument. Otherimplementations may include point contact surfaces.

FIGS. 47 through 79 illustrate alternative implementations ofpatient-matched instruments and non-patient-matched, standard,instruments that can be used together. FIGS. 47 through 50 illustrate animplementation of a patient-matched instrument 1900 that includes guidefeatures 1910 (such as cutting guides) as well as mounting features1915, 1916 for attachment of additional components, such as standardinstrumentation. The patient-matched instrument shown in FIGS. 47through 50 includes patient-matched surfaces 1906 on the main body andoutriggers that are customized to a particular patient's anatomy, tofacilitate correctly positioning and orienting the instrument on thepatient's anatomy. In the particular implementation shown in FIGS. 47through 50, the patient-matched surfaces 1906 of the instrument 1900 aresufficient to position and orient the instrument in all of the degreesof freedom relevant to the tibial resections of a bi-cruciate retainingknee arthroplasty procedures, although, in other implementations, thesesurfaces or point contact surfaces and or other attributes of theinstrument may only be relevant to establishing some of the degrees offreedom relevant to such a procedure or other procedures.

The patient-matched instrument 1900 shown also includes guide slots 1910for guiding a saw blade or blades. In this particular implementation,the guide slots 1910 guide the two vertical eminence resections and thevertical anterior eminence resection of a bi-cruciate retainingarthroplasty procedure, although, in other implementations, othernumbers, positions, orientations and other types of guide features 1910could be included in the patient-matched instrument 1900 forfacilitating bi-cruciate retaining knee arthroplasty procedures or othertypes of knee, hip, or other orthopaedic procedures on other anatomy orjoints. In still other implementations, the patient-matched instrument1900 does not include any guide features 1910, but rather simply servesas a mount for securing and/or positioning a standard instrument orinstruments that are mounted or otherwise associated with thepatient-matched instrument.

The patient-matched instrument shown in FIGS. 47 through 50 includesmounting features 1915, 1916 for facilitating the association ofadditional components with the patient-matched instrument 1900. Theparticular instrument shown in FIGS. 47 through 50 includes severalprotrusions that are positioned, oriented and shaped to interact withstructures of the additional component, the protrusions includingseveral cylindrical pins 1915 as well as a substantially planarprotrusion 1916. FIG. 51 shows an alternative implementation where theplanar protrusion 2016 is an elongated tongue that includes a frangibleportion 2017. In some implementations, the frangible protrusion ortongue 2016, when attached, may facilitate positioning and orienting afirst instrument with respect to the patient-matched instrument, and,after removal, the remaining portion of the tongue 2016 may facilitatepositioning and orienting a second instrument. As shown in FIGS. 47through 51, other portions of the patient-matched instrument 1900 canalso be frangible. The patient-matched instruments 1900, 2000 of FIGS.47 through 51 also include a vertical aperture 1917 for receiving amounting bolt, as described further below. The patient-matchedinstruments 1900, 2000 of FIGS. 47 through 51 also include apertures forreceiving pins or other devices for fastening the patient-matchedinstrument to the patient's anatomy.

FIGS. 52 through 60 illustrate an implementation of a standard,ion-patient-matched instrument 2100 that may be used in conjunction withthe patient matched instruments of FIGS. 47 through 51. The standardinstrument of FIGS. 52 through 60 includes a slot 2118 (FIG. 55) andseveral apertures 2119 extending at least partially through the body ofthe instrument that are sized, positioned and oriented to interact withthe various protrusions of the patient-matched instruments 1900, 2000 ofFIGS. 47 through 51 to facilitate securing, or at least positioning andorienting, the standard instrument with respect to the patient-matchedinstrument. In the particular implementation shown, the standardinstrument 2100 can only be mounted to the patient-matched instrument ina single position and orientation such that the position and orientationof the patient-matched instrument 2100 (when placed on the patient'sanatomy) establishes the position and orientation of the standardinstrument 2100 (with respect to the patient's anatomy). In otherimplementations, the position and/or orientation of the standardinstrument 2100 can be adjusted in at least some degrees of freedom withrespect to the patient-matched instrument, even when the standardinstrument 2100 is mounted to the patient-matched instrument. Forinstance, in some implementations, the standard instrument 2100 may beable to pivot and slide to at least some extent on the tongue of thepatient-matched instrument, and the connection between the twocomponents could function as a planar joint. In other implementations,the multiple apertures in the standard instrument 2100 may provideseveral discrete different positions and/or orientations in which tomount the standard instrument 2100 on the patient-matched instrument. Instill other implementations, the position and/or orientation of thestandard instrument 2100 with respect to the patient-matched instrumentcould be adjusted in other ways.

The standard instrument 2100 of FIGS. 52 through 60 also includes alocking mechanism 2103 for securing components positioned in the slot2118 of the instrument, such as a tongue or other protrusion extendingfrom the patient-matched instrument, or a feature of otherpatient-matched or non-patient-matched instrumentation. In theparticular implementation of FIGS. 52 through 60, the standardinstrument 2100 includes a cam mechanism that is actuated by moving apaddle arm 2108 from an unlocked position (see FIG. 57) to a lockedposition (see FIG. 58). The standard instrument 2100 of FIGS. 52 through60 also includes a threaded aperture 2109 for receiving a mounting boltas a mechanism for further or alternatively securing the standardinstrument to a patient-matched instrument and/or other component.

The standard instrument 2100 of FIGS. 52 through 60 includes severalcylindrical openings 2116 for receiving bone pins to secure theinstrument to the patient's anatomy. In the particular implementationshown, the instrument includes multiple pairs of parallel openingsextending from an anterior face of the instrument to a posterior face ofthe instrument, which may facilitate discrete adjustment of theinstrument with respect to the patient's anatomy (e.g. allowing fordiscrete adjustment of superior/inferior positioning of the instrumentto adjust depth of cut or for other adjustments or purposes). Theinstrument of FIGS. 52 through 60 also includes an oblique opening 2117,also for receiving a bone pin, to further secure the instrument onto thepatient's anatomy. As stated above, in some implementations, some or allof these openings can be used for other purposes, such as receivingcylindrical protrusions on the patient-matched instrument to facilitatethe positioning and orienting of the standard instrument with respect tothe patient-matched instrument.

The standard instrument of FIGS. 52 through 60 includes a planarsuperior face 2102, which, in some implementations, may function as aresection guide for guiding a planar cutting device such as anoscillating saw blade. In the particular implementation shown, theplanar face is sized, positioned and oriented on the instrument tofacilitate a planar medial resection of the proximal tibia, althoughother configurations are also possible for guiding other resections. Inthe particular implementation shown, the standard instrument 2100 ofFIGS. 52 through 60 can be used in conjunction with the additionalcomponent 2400 shown in FIGS. 61 through 67 to further limit themovement of the saw blade to a single plane.

The standard instrument 2100 of FIGS. 52 through 60 also includes anattachment 2112 site for securing an alignment rod to the instrument. Inthe particular implementation shown, the instrument includes a channel2112 that can slidingly receive the alignment rod, and a knurled bolt2113 for securing the alignment rod into the channel. Other structuresand mechanisms could also be used to secure an alignment rod to theinstrument if desired. In some implementations, the alignment rod can beused at appropriate points in the surgical procedure to confirmalignment of the instrumentation with respect to the patient's anatomy,such as the anatomic and/or mechanical axes of the patient's femurand/or tibia.

FIGS. 61 through 71 illustrate a non-limiting example of a method ofusing the patient-matched and standard instruments of FIGS. 47 through67 to perform some of the steps of a bi-cruciate retaining arthroplastyprocedure, although, in other implementations, instrumentation havingsome or all of the features of the described implementations could beused for other joint arthroplasty or other types of orthopaedicprocedures.

FIG. 61 shows a patient-matched instrument 2300 that has been customizedto the anatomy of a specific patient such that the instrument conformsto or references the patient's anatomy (in this implementation, theright, proximal tibia) to establish a desired position and orientationof the instrument with respect to the patient's anatomy. In theparticular implementation shown, the patient-matched instrument includespatient-matched contact surfaces on the anatomy facing surfaces on theinstrument (not shown in this particular figure) that were establishedusing MRI data and pre-selected positions and orientations of thedesired resections to the bone (or desired final position andorientation of the tibial implant(s)) and was manufactured usingselective laser sintering technologies, although, in otherimplementations, other data collection, processing, and manufacturingmethods could be used to customize the instrument to the patient'sanatomy.

FIG. 62 shows the connection of the standard instrument 2100 of FIG. 52to the patient-matched instrument 2300 of FIG. 61 using a mounting bolt2301. In the particular implementation shown, the standard instrument2100 is connected to the patient-matched instrument before positioningthe construct on the patient's anatomy, although, in otherimplementations, the patient-matched instrument could be positioned onthe anatomy before the standard instrument is connected. FIG. 63illustrates the patient-matched instrument/standard instrument construct2400 positioned on the patient's proximal tibia 100, using theconforming surfaces and/or point contact features on the bone-facingside of the patient-matched instrument to establish the proper positionand orientation of the construct with respect to the patient's anatomy.If desired, the surgeon may confirm the proper position and orientationof the construct on the patient's tibia 100 at this point by attachingan alignment rod to the construct and checking alignment relative to themechanical and/or anatomic axes of the patient's tibia and/or femur.

FIG. 64 shows the patient-matched/standard instrument 2400 constructsecured to the patient's anatomy using several bone pins 2464, 2465. Inthis particular implementation, there are two vertical pins 2455associated with the outriggers of the patient-matched instrument, twohorizontal pins 2464 passing through the main body of thepatient-matched instrument, two horizontal parallel pins 2465 passingfirst through standard instrument and second through the patient matchedinstrument (the reverse is an alternative implementation), and oneoblique pin 2466 passing through the standard instrument. In otherimplementations, other combinations of pins or other fastening devicescould be used to secure the construct to the patient's anatomy.

In the particular implementation shown, after thepatient-matched/standard instrument construct is secured the proximaltibia 100, the guides 2310 incorporated into the patient-matchedinstrument 2300 are used to guide the vertical eminence resections andthe anterior eminence vertical resection. In some implementations, areciprocating saw is used for the vertical eminence resections and achisel is used for the vertical anterior eminence resection. In theparticular implementation shown, the horizontal pins 2464 that securethe patient-matched instrument to the tibia also function to limit thedepth of cut of these resections. FIG. 65 illustrates the proximal tibia100 and patient-matched/standard instrument construct 2400 after theseresections have been completed.

As shown in FIGS. 66 through 69, after these resections are completed,the patient-matched instrument 2300 can be unbolted from the standardinstrument and portions of the patient-matched instrument 2300 that areno longer needed could be broken away along frangible connections. Inother implementations, the patient-matched instrument need not befrangible, and could be designed to be partially or totally removed fromthe construct 2400 in other manners. For instance, in someimplementations, the bone pins 2464, 2465 could function as placeholders to allow the entire patient-matched/standard instrumentconstruct 2400 to be removed from the anatomy, disassembled, and onlythe standard instrument replaced onto the anatomy. In still otherimplementations, the patient-matched instrument could first bepositioned on the anatomy without the standard instrument, and could beused to make the initial resections and position the bone pins, and thenremoved from the patient's anatomy and replaced with the standardinstrument.

In some implementations, removal of portions of the patient-matchedinstrument facilitates access to other features and/or functionality ofone or both of the patient-matched or standard instruments. Forinstance, in the particular implementation illustrated, particularlyFIG. 70, removal of portions of the patient-matched instrument allowsthe supplemental component 2200 (FIG. 73) to be secured to the standardinstrument 2100. As shown in FIG. 70, the supplemental component 2200 isconfigured to accommodate the medial horizontal pin while also defininga planar surface 2210 that interfaces with a superior surface on thecutting blade to help guide the horizontal plateau resection. In theparticular implementation shown, the planar superior surface 2210 of thestandard instrument 2200 (in conjunction with the planar inferiorsurface of the supplemental component) control the depth and posteriorslope of the resection and the horizontal pin controls the medial extentand internal/external rotation of the resection. Other guide structuresand techniques are also possible. For instance, in some implementations,the medial plateau resection could be performed without the use of thesupplemental component. FIG. 71 shows the tibia 100 after the medialplateau resection.

As shown in FIG. 72, the standard component, particularly the planarsuperior surface of the standard component, may be used in someimplementations to also guide the horizontal anterior eminenceresection. In some implementations, the vertical and/or horizontalanterior eminence resections are not performed until after the medialresections have been evaluated and/or balanced.

FIGS. 61 through 72 only show some of the steps of a bi-cruciateretaining knee arthroplasty procedure, and the remainder of theprocedure may be completed using these or other standard and/orpatient-matched instrumentation.

Additions, deletions, substitutions, modifications and other changes maybe made to the non-limiting implementations described herein withoutdeparting from the scope or spirit of the present disclosure.

The invention claimed is:
 1. A patient matched tibial cutting block,comprising: a surface or point contact feature adapted to at leastpartially conform to or reference a patient specific anatomy wherein apatient specific surface is established in pre-surgical planning basedon imaging data of the patient specific anatomy; a plurality ofeminence-preserving guide slots and a plurality of plateau guide slots,wherein the guide slots are configured for guiding movement of cuttingtools relative to the patient specific anatomy; and one or moreapertures configured to guide placement of provisional fixation pinsalong a resection plane corresponding with one or more of the plateauguide slots.
 2. The patient matched tibial cutting block of claim 1,wherein the one or more apertures contain position control elementsconfigured to control a depth of the provisional fixation pins.
 3. Thepatient matched tibial cutting block of claim 1, further comprisingretractor features detachably coupled to the patient matched tibialcutting block and configured to retain soft tissue away from theplurality of guide slots.
 4. The patient matched tibial cutting block ofclaim 1, wherein the plurality of guide slots include surfaces thatfacilitate horizontal medial and lateral plateau resections and verticalmedial and lateral eminence resections of a proximal tibia.
 5. Thepatient matched tibial cutting block of claim 1, wherein the pluralityof eminence guide slots configured for guiding the movement of thecutting tools relative to the patient specific anatomy form plateau andeminence resections of the patient specific anatomy.
 6. The patientmatched tibial cutting block of claim 1, wherein each of the pluralityof eminence-preserving guide slots extend in the same anterior-posteriordirection.
 7. A system, comprising: the patient matched tibial cuttingblock of claim 1; and a standard instrument attachable to the patientmatched tibial cutting block to assist in the configuration and guidanceof a cutting tool during a bone resection procedure.
 8. A patientspecific tibial cutting guide, comprising: a central portion configuredto at least partially overlay anterior and superior portions of aproximal tibia; a plurality of outrigger portions extending from thecentral portion and configured to at least partially overlay medial andlateral articulation surfaces of the proximal tibia; and a plurality ofwing portions extending medially and laterally from the central portionand configured to extend at least partially around medial and lateralsides of an anterior face of the proximal tibia, wherein the centralportion and the plurality of outrigger portions define guide slotsconfigured for guiding a cutting tool to form vertical and anterioreminence-preserving resections of the proximal tibia and the pluralityof wing portions define guide slots for guiding a cutting tool to formhorizontal plateau resections of the proximal tibia; and wherein each ofa plurality of the vertical eminence-preserving guide slots extends inthe same anterior-posterior direction.
 9. The patient specific tibialcutting guide of claim 8, wherein one or more of the central portion,the plurality of outrigger portions, and the plurality of wing portionscomprises one or more surfaces or point contacts adapted to at leastpartially conform to or reference a corresponding surface of theproximal tibia, wherein the one or more surfaces are established inpre-surgical planning based on imaging data of the proximal tibia. 10.The patient specific tibial cutting guide of claim 8, further comprisingone or more apertures defined in the central portion or the plurality ofoutrigger portions and configured to guide placement of provisionalfixation pins.
 11. The patient specific tibial cutting guide of claim 8,wherein the plurality of wing portions comprise retractor featuresconfigured to retain soft tissue away from the guide slots.
 12. Thepatient specific tibial cutting guide of claim 11, wherein the retractorfeature extends from the distal end of each wing portion.
 13. Thepatient specific tibial cutting guide of claim 8, further comprisingreinforcing elements at least partially embedded in one or more of thecentral portion, the plurality of outrigger portions, and the pluralityof wing portions.
 14. A system, comprising: the patient specific tibialcutting guide of claim 8; and a standard instrument attachable to thepatient specific tibial cutting guide to assist in the configuration andguidance of a cutting tool during a bone resection procedure.
 15. Amethod of resectioning a proximal tibia, comprising: securing a patientmatched instrument to a patient's proximal tibia; and using the patientmatched instrument to guide one or more cutting guides relative to theproximal tibia to form at least a medial vertical eminence-preservingresection, a lateral vertical eminence-preserving resection, and ananterior vertical eminence-preserving resection.
 16. The method of claim15, wherein using the patient matched instrument to guide one or morecutting guides relative to the proximal tibia forms both horizontalplateau resections and the vertical eminence-preserving resections. 17.The method of claim 16, wherein the horizontal plateau resectionsinclude medial and lateral horizontal plateau resections.
 18. The methodof claim 15, wherein securing the patient matched instrument to thepatient's proximal tibia comprises using one or more fixation pins tosecure the instrument in a particular location relative to the tibia,and wherein one or more holes formed in the tibia during the securingstep are removed during resectioning.